In class A airspace, the minimum altitude separation is 2000 ft between which flight levels? (non DRVSM)

• A. FL290 FL410
• B. FL180 FL260
• C. FL200 FL300
• D. FL180 FL290

Answer: (A)

In Class A airspace, vertical separation minima depend on whether Reduced Vertical Separation Minimum (RVSM) is in effect. Without RVSM, the standard separation is 2000 feet; with RVSM, between the flight levels FL290 and FL410 the separation is reduced to 1000 feet.

The question asks which flight levels define the region where the 2000-foot separation applies in non-RVSM conditions. The pair that marks the boundaries of the RVSM region is FL290 and FL410. Outside this band (below FL290 and above FL410), the 2000-foot separation is used, so those two levels delineate where the non-RVSM minimum applies.

The other options do not represent the RVSM boundary and therefore do not identify the correct region where the 2000-foot separation applies in non-RVSM airspace.